We've been using one for over 10 years and works great for our very small space. It's rated 1,000/1,500 watts low/high heat. We rarely camp in very cold weather, so Low setting is usually enough to keep us warm. High setting has been plenty to overnight in temperatures down into the high 20s.
Current should only be ~ 9 to 13 Amps, so we can run other items like microwave at same time off 30-Amp service.
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